Above the front door of Phil Gustafson’s house on San Jose’s Martin Avenue, to the right of the palm tree that hugs the roof, hangs a rusty horseshoe. It might have been Gustafson’s last nod to luck in a life that edged toward hibernation.

A bearded man just short of 6 feet tall, with long salt-and-pepper hair hidden by a baseball cap, Gustafson could be seen walking to the grocery store on San Carlos Street or driving his beaten-up Saab 900 convertible to Trader Joe’s, even with outdated tags.

He wasn’t unfriendly. At least one neighbor recalled him as kind and intelligent. But he wasn’t chatty, either. He did nothing to arrest the decay of his house, which old-timers remember as a one-time Prohibition-era booze cabin, set back 100 feet from the street.

There had been a woman once, back in the ’80s, when Gustafson bought the house. But she was long gone, and so was any pretense of upkeep. When the neighbors told him his big tree needed trimming, he shrugged and said to go ahead and cut the overhang.

His hibernation ended last week, when the newspapers started piling up on the driveway. The postman recognized that the mail wasn’t being picked up. A package from Amazon sat on his front steps. That wasn’t like Gustafson: He didn’t take vacations.

Finally, the police cars swarmed down Martin, and the cops kicked down the locked front door. They found Gustafson dead in his bed. His computer was on. He hadn’t been seen for more than a week. And he had aged noticeably. From time to time, the neighbors heard him coughing.

A case number

Now the 67-year-old Massachusetts native is a police case number. The coroner’s office says it is awaiting a formal identification. There’s no sign of foul play. Yet Gustafson’s passing haunts me. He died alone, without family nearby, in his version of a cave. The sadness in that doesn’t stop.

I know from the trail on the Web that he was a smart and witty man with an exceptional range of knowledge, conversant about nuclear fission, old battleships, carburetors and computer security. He had once been an employee of Saber Technology in San Jose, a veteran Unix programmer.

Like a lot of geeks, he had a love for word play. He signed himself Phil “a pox on dim-bulb middle names” Gustafson. He warned that his satirical comments might not be identified as such.

And he once offered a long treatise on Rattray’s tobacco, a Scottish brand. (One of his recommendations was No. 7, Accountant’s Mixture).

Battleship knowledge

When one poster asked about the location of battleships, Gustafson replied with extraordinary precision. He explained that The HMS Victory was in concrete at Portsmouth, and that fragments of the Swedish liner Vasa, which sank on its maiden voyage in 1628, were being restored indoors in Stockholm.

Gustafson made his own choices in life, and perhaps for him there was a kind of liberty in retreating into his refuge on Martin Avenue. Yet I’m bothered by someone exiting alone, with only the piled-up newspapers and the overflowing mail to announce his passing.

Fundamentally, we are social beings, and in his early exchanges, you could tell Gustafson was too, eager to fill in gaps in knowledge. In his cabin, he might have been free of encumbrances, unworried about appearances. But his horseshoe didn’t spell lucky.

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